<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>滑动阴影按钮</title>
</head>

<body>

    <div class="intro">
        <div class="intro__actions">

            <a href="https://htmlburger.com/" class="btn btn--black">
                <span>来源</span>
            </a>
        </div>
    </div>
    <style>
        .intro {
            background: #FFE26D;
            padding: 50px;
        }

        .intro__actions {
            display: flex;
        }

        .btn {
            position: relative;
        }

        .btn>span {
            position: relative;
            display: inline-block;
            height: 50px;
            padding: 0 28px;
            border: 2px solid #353535;
            border-radius: 5px;
            line-height: 46px;
            text-align: center;
            z-index: 2;
        }



        .btn:before {
            content: '';
            position: absolute;
            width: 100%;
            height: 100%;
            border-radius: 5px;
            top: 10px;
            left: 10px;
            -webkit-transition: top .15s, left .15s;
            -o-transition: top .15s, left .15s;
            transition: top .15s, left .15s;
            pointer-events: none;
            background: rgba(255, 255, 255, 0.4);
        }


        .intro a:hover {
            text-decoration: none;
        }

        .intro .btn:hover:before {
            top: 0;
            left: 0;
        }
    </style>

    https://htmlburger.com/
</body>

</html>